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Neuroepidemiology 2010;34:123–129

Geographic Variation in One-Year Recurrent Ischemic Stroke Rates for Elderly Medicare Beneficiaries in the USA

Allen N.B.a, f · Holford T.R.b · Bracken M.B.c · Goldstein L.B.d · Howard G.e · Wang Y.a · Lichtman J.H.a
Divisions of aChronic Disease Epidemiology and bBiostatistics, Department of Epidemiology and Public Health, and cCenter for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, Conn., dDepartment of Medicine (Neurology), Duke Stroke Center, Center for Clinical Health Policy Research, Duke University and Durham VAMC, Durham, N.C., eDepartment of Biostatistics, School of Public Health, University of Alabama at Birmingham, Birmingham, Ala., and fDepartment of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Ill., USA
email Corresponding Author

 goto top of outline Key Words

  • Stroke, recurrent
  • Small-area analysis
  • Variation, geographic
  • Recurrence

 goto top of outline Abstract

Background: While geographic disparities in stroke mortality are well documented, there are no data describing geographic variation in recurrent stroke. Accordingly, we evaluated geographic variations in 1-year recurrent ischemic stroke rates in the USA with adjustment for patient characteristics. Methods: One-year recurrent stroke rates for ischemic stroke (International Classification of Diseases, 9th Revision codes 433, 434 and 436) following hospital discharge were calculated by county for all fee-for-service Medicare beneficiaries from 2000 to 2002. The rates were standardized and smoothed using a bayesian conditional autoregressive model that was risk-standardized for patients’ age, gender, race/ethnicity, prior hospitalizations, Deyo comorbidity score, acute myocardial infarction, congestive heart failure, diabetes, hypertension, dementia, cancer, chronic obstructive pulmonary disease and obesity. Results: The overall 1-year recurrent stroke rate was 9.4% among 895,916 ischemic stroke patients (mean age: 78 years; 56.6% women; 86.6% White, 9.7% Black and 1.2% Latino/Hispanic). The rates varied by geographic region and were highest in the South and in parts of the West and Midwest. Regional variation was present for all racial/ethnic subgroups and persisted after adjustment for individual patient characteristics. Conclusions: Almost 1 in 10 hospitalized ischemic stroke patients was readmitted for an ischemic stroke within 1 year. There was heterogeneity in recurrence patterns by geographic region. Further work is needed to understand the reasons for this regional variability.

Copyright © 2010 S. Karger AG, Basel

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 goto top of outline Author Contacts

Judith Lichtman
Yale University School of Medicine
PO Box 208034
New Haven, CT 06520-8034 (USA)
Tel. +1 203 785 3025, Fax +1 203 785 6980, E-Mail

 goto top of outline Article Information

Received: July 12, 2009
Accepted: November 10, 2009
Published online: January 13, 2010
Number of Print Pages : 7
Number of Figures : 2, Number of Tables : 2, Number of References : 36
Additional supplementary material is available online - Number of Parts : 1

 goto top of outline Publication Details


Vol. 34, No. 2, Year 2010 (Cover Date: February 2010)

Journal Editor: Feigin V.L. (Auckland)
ISSN: 0251-5350 (Print), eISSN: 1423-0208 (Online)

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